I actually have considered making them, they are pretty cool unit, and not that complicated to excecute. Tought once I get back to finish Valkia, I will continue other mods work for awhile, so no big updates in mercs after her for awhile. Suggestions like this, and feedback are more than welcome ofcourse.
I'm not sure about unofficial units yet, I tought about making more Amazons units coming alongside Anakonda from unofficial army-book, when I started them, and checked Nippons and Tilea's unofficial books too. But there is so many official units/heroes to choose from, that I believe I will stay in them for now.